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Abstract:

A transmission line assembly for transmission and distribution of high
voltage power which comprises a conductor, a separate messenger member
and coupling means. The conductor has a predetermined length. The
separate messenger member has a predetermined length. The coupling means
couples the messenger to the conductor to the messenger. The messenger
member and the conductor remain structurally separate from each other and
functionally independent.

Claims:

1. A transmission line assembly for transmission and distribution of high
voltage power comprising: a conductor having a predetermined length; a
separate messenger member having a predetermined length; means for
coupling the messenger to the conductor, such that the messenger member
remains structurally separate from the conductor and functionally
independent thereof.

2. The transmission line assembly of claim 1 wherein the conductor
comprises a substantially circular cross-section which includes a
plurality of strands uniformly dispersed therethrough.

3. The transmission line assembly of claim 1 wherein the messenger
comprises an insulative member including a plurality of fibers embedded
in a glass matrix.

4. The transmission line assembly of claim 1 wherein the plurality fibers
comprises one or more of the following fibers, carbon fibers, basalt
fibers, s-glass fibers, r-glass fibers, s2-glass fibers or other glass
fibers.

5. The transmission line assembly of claim 1 wherein the conductor is
structurally configured to transmit between 2400 V and 765,000 V.

6. The transmission line assembly of claim 1 wherein the conductor and
the messenger member are spaced apart from each other a predetermined
distance, and wherein the coupling means facilitates the maintenance of
the separation of the messenger relative to the conductor.

7. The transmission line assembly of claim 6 wherein the coupling means
comprises a pair of bracket members, each bracket member includes a
conductor indentation and a messenger indentation, whereupon positioning
of the bracket members in operable association, the conductor indentation
of each of the bracket members cooperate to surround and capture the
conductor, the messenger indentation of each of the bracket members
cooperate to surround and capture the messenger member, and, an
attachment assembly configured to retain the bracket members in operable
engagement.

8. The transmission line assembly of claim 7 wherein the attachment
assembly comprises a fastener attachable to each of the bracket members.

9. The transmission line assembly of claim 6 wherein the coupling means
comprises a bracket member having a messenger indentation at a first end
thereof and a conductor indentation at the other end thereof, a messenger
clamp assembly is pivotably coupled to bracket member proximate the
messenger indentation, whereupon the messenger clamp cooperates with the
bracket member to retain the messenger within the messenger indentation,
and, a conductor clamp assembly is pivotably coupled to the bracket
member proximate the conductor indentation, whereupon the conductor clamp
cooperates with the bracket member to retain the conductor within the
conductor indentation.

10. The transmission line assembly of claim 9 wherein at least one of the
messenger indentation and the conductor indentation includes a liner or a
resilient member to preclude damage to the respective one of the
conductor and messenger relative to the bracket member.

11. The transmission line assembly of claim 6 wherein the coupling means
comprises a messenger tray assembly defining a channel structurally
configured to receive the messenger, a conductor tray assembly defining a
channel structurally configured to receive the conductor, and a pivotable
coupling assembly which facilitates the pivotable coupling of the
messenger tray assembly relative to the conductor tray assembly.

12. The transmission line assembly of claim 11 wherein at least one of
the messenger tray assembly and the conductor tray assembly further
includes a clamp member configured to clamp the respective one of the
conductor and the messenger thereto.

13. The transmission line assembly of claim 12 wherein the pivotable
coupling means comprises a pair of ear members on each of the messenger
tray assembly and the conductor tray assembly, and a pivoting connector
pivotably extending through each of the ear members, to in turn,
facilitate pivoting of the messenger tray assembly relative to the
conductor tray assembly.

14. The transmission line assembly of claim 13 wherein the pivotable
coupling means comprises at least one link which is pivotably connected
at the first end to the conductor tray assembly and pivotably connected
at the second end to the messenger tray assembly.

15. The transmission line assembly of claim 1 further comprising a second
conductor, the first conductor, the second conductor and the messenger
member are spaced apart from each other a predetermined distance, and
wherein the coupling means facilitates the maintenance of the separation
of the messenger relative to the conductor, the coupling member comprises
a frame member having a central region and opposing wing members, the
messenger member is coupled to the central region of the frame member,
and each conductor is pivotably connected to opposing wing members of the
frame member.

16. The transmission line assembly of claim 1 wherein the coupling means
comprises a flexible housing member extending over the conductor and the
messenger, and an armor grip clamp assembly comprising a pair of
semi-circular clamps extending around a portion of the flexible housing
member and coupling to each other to releasably retain the same.

17. The transmission line assembly of claim 1 wherein coupling means
comprises a flexible liner which are structurally configured to maintain
the messenger member and the conductor in a spaced apart configuration,
and a clamp member extending thereover to releasably maintain the
flexible liner relative to the messenger and the conductor.

18. The transmission line assembly of claim 1 wherein the coupling means
comprises the wrapping of the conductor relative to the messenger in a
helical winding, along the length thereof.

[0003] The invention relates in general to a transmission cable intended
for the transmission and distribution of electrical power, and typically,
high voltage electrical power. More particularly, the transmission cable
of the present invention separates the mechanical strength member from
the electrical current carrying member, such that each can be designed
and configured without dependence on the other.

[0004] 2. Background Art

[0005] The demand for transmission and distribution cables increases with
the greater demand for electricity. As the appetite for power increases,
new electrical cables continue to be installed. Additionally, to increase
capacity, other electrical installations are rewired with cables of
greater capacity.

[0006] Traditionally, such electrical cables comprise a central stranded
steel core which is wrapped in a stranded aluminum conductor. Such cables
have been utilized for decades with very little change. Amongst other
drawbacks, such cables are susceptible to excessive sag in certain
climates and under certain operating conditions. Furthermore, such cables
are susceptible to corrosion in other environments.

[0007] To combat the shortcomings, other composite based solutions have
been developed. Certain such solutions are described in U.S. Pat. No.
7,060,326; U.S. Pub. Nos. 2004-0131834; 2004-0131851; 2005-0227067;
2005-0129942; 2005-0186410; 2006-0051580; U.S. Prov. Pat. App. No.
60/374,879; and PCT Pub. No. WO 03/091008, the entire disclosures of each
of the foregoing are incorporated herein by reference in their entirety.
Such solutions have replaced the central steel stranded core with a
composite material having a core component formed from a carbon fiber
material embedded within a matrix and an outer component formed from a
fiber material other than carbon embedded within a resin. The core is
formed by pultruding the various fibers through pultrusion dies.

[0008] Despite these additional developments, the continuing drawback
associated with the foregoing conductor solutions is that the mechanical
strength member is intertwined and inseparably coupled with the current
carrying conductor. As such, the current carrying conductor is limited in
construction due to the considerations of its mechanical strength.
Additionally, the mechanical strength member is limited by its
compatibility with the conductor. For example, due to the relationship
between the conductor and the core, the heat requirements of the core are
quite elevated, due to the proximity thereof with the conductor.
Additionally, as the conductor and the core are both spliced and dead
ended together, it is necessary to consider both the conductor and the
core when configuring such a splice or a dead end. Such considerations
often lead to a compromised solution.

[0009] It is another object of the present invention to separate the
mechanical strength member from the current carrying conductor in
transmission lines.

[0010] It is another object of the invention to provide independently
designed cnad configured mechanical strength members and current carrying
conductors in transmission lines.

[0011] These objects as well as other objects of the present invention
will become apparent in light of the present specification, claims, and
drawings.

SUMMARY OF THE INVENTION

[0012] The invention is directed to a transmission line assembly for
transmission and distribution of high voltage power which comprises a
conductor, a separate messenger member and coupling means. The conductor
has a predetermined length. The separate messenger member has a
predetermined length. The coupling means couples the messenger to the
conductor to the messenger. As such, the messenger member and the
conductor remain structurally separate from each other and functionally
independent.

[0013] In a preferred embodiment, the conductor comprises a substantially
circular cross-section which includes a plurality of strands uniformly
dispersed therethrough.

[0014] In another preferred embodiment, the messenger comprises an
insulative member including a plurality of fibers embedded in a glass
matrix.

[0015] In another preferred embodiment, the plurality fibers comprises one
or more of the following fibers, carbon fibers, basalt fibers, s-glass
fibers, r-glass fibers, s2-glass fibers or other glass fibers.

[0016] Preferably, the conductor is structurally configured to transmit
between 2400 V and 765,000 V.

[0017] In another preferred embodiment, the conductor and the messenger
member are spaced apart from each other a predetermined distance. The
coupling means facilitates the maintenance of the separation of the
messenger relative to the conductor.

[0018] In pone such preferred embodiment, the the coupling means comprises
a pair of bracket members. Each bracket member includes a conductor
indentation and a messenger indentation. Upon positioning of the bracket
members in operable association, the conductor indentation of each of the
bracket members cooperate to surround and capture the conductor.
Similarly, the messenger indentation of each of the bracket members
cooperate to surround and capture the messenger member. An attachment
assembly configured to retain the bracket members in operable engagement.

[0019] In a preferred embodiment, the attachment assembly comprises a
fastener attachable to each of the bracket members.

[0020] In a preferred embodiment, the coupling means comprises a bracket
member having a messenger indentation at a first end thereof and a
conductor indentation at the other end thereof. A messenger clamp
assembly is pivotably coupled to bracket member proximate the messenger
indentation. The messenger clamp cooperates with the bracket member to
retain the messenger within the messenger indentation. A conductor clamp
assembly is pivotably coupled to the bracket member proximate the
conductor indentation. The conductor clamp cooperates with the bracket
member to retain the conductor within the conductor indentation.

[0021] In another preferred embodiment, at least one of the messenger
indentation and the conductor indentation includes a liner or a resilient
member to preclude damage to the respective one of the conductor and
messenger relative to the bracket member.

[0022] In another preferred embodiment, the coupling means comprises a
messenger tray assembly defining a channel structurally configured to
receive the messenger, a conductor tray assembly defining a channel
structurally configured to receive the conductor, and a pivotable
coupling assembly which facilitates the pivotable coupling of the
messenger tray assembly relative to the conductor tray assembly.

[0023] In yet another preferred embodiment, at least one of the messenger
tray assembly and the conductor tray assembly further includes a clamp
member configured to clamp the respective one of the conductor and the
messenger thereto.

[0024] In a preferred embodiment, the pivotable coupling means comprises a
pair of ear members on each of the messenger tray assembly and the
conductor tray assembly. A pivoting connector pivotably extends through
each of the ear members, to in turn, facilitate pivoting of the messenger
tray assembly relative to the conductor tray assembly.

[0025] In a preferred embodiment, the pivotable coupling means comprises
at least one link which is pivotably connected at the first end to the
conductor tray assembly and pivotably connected at the second end to the
messenger tray assembly.

[0026] In a preferred embodiment, the apparatus further comprises a second
conductor. The first conductor, the second conductor and the messenger
member are spaced apart from each other a predetermined distance. The
coupling means facilitates the maintenance of the separation of the
messenger relative to the conductor. The coupling member comprises a
frame member having a central region and opposing wing members. The
messenger member is coupled to the central region of the frame member,
and each conductor is pivotably connected to opposing wing members of the
frame member.

[0027] In a preferred embodiment, the coupling means comprises a flexible
housing member extending over the conductor and the messenger. An armor
grip clamp assembly comprises a pair of semi-circular clamps extending
around a portion of the flexible housing member and coupling to each
other to releasably retain the same.

[0028] In another preferred embodiment, the coupling means comprises a
flexible liner which is structurally configured to maintain the messenger
member and the conductor in a spaced apart configuration. A clamp member
extends over the flexible liner to releasably maintain the flexible liner
relative to the messenger and the conductor.

[0029] In yet another preferred embodiment, the coupling means comprises
the wrapping of the conductor relative to the messenger in a helical
winding, along the length thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The invention will now be described with reference to the drawings
wherein:

[0031]FIG. 1 of the drawings comprises a side elevational view of a
typical installation of a transmission line of the present invention,
showing, in particular, a span between towers;

[0032]FIG. 2 of the drawings comprises a partial side elevational view of
an embodiment of the transmission line of the present invention, showing,
in particular, an embodiment of the coupling means;

[0033]FIG. 3 of the drawings comprises a perspective view of the coupling
means of the embodiment shown in FIG. 2;

[0034]FIG. 4 of the drawings comprises a front elevational view of
another embodiment of the coupling means of the present invention;

[0035]FIG. 5 of the drawings comprises a side elevational view of the
embodiment of the coupling means shown in FIG. 4, shown in a coupled
configuration;

[0036]FIG. 6 of the drawings comprises a side elevational view of the
embodiment of the coupling means shown in FIG. 4, shown in an open
configuration ready for the receipt of a messenger and a conductor;

[0037]FIG. 7 of the drawings comprises a perspective view of the
transmission line of the present invention, showing, in particular,
another embodiment of the coupling means of the present invention;

[0038]FIG. 8 of the drawings comprises a front elevational view of a
transmission line of the present invention, showing, in particular,
another embodiment of the coupling means;

[0039]FIG. 9 of the drawings comprises a front elevational view of a
transmission line of the present invention, showing, in particular,
another embodiment of the coupling means for coupling a multiple number
of conductors from a single messenger;

[0040]FIG. 10 of the drawings comprises a side elevational view of the
transmission line of the present invention, showing, in particular, the
coupling means of FIG. 9;

[0041]FIG. 11 of the drawings comprises a side elevational view of the
transmission line of the present invention, showing, in particular,
another embodiment of the coupling means;

[0042]FIG. 12 of the drawings comprises a cross-sectional view of the
transmission line shown in FIG. 11;

[0043]FIG. 13 of the drawings comprises a side elevational view of the
transmission line of the present invention, showing, in particular,
another embodiment of the coupling means; and

[0044]FIG. 14 of the drawings comprises a side elevational view of the
transmission line of the present invention, showing, in particular,
another embodiment of the coupling means.

DETAILED DESCRIPTION OF THE INVENTION

[0045] While this invention is susceptible of embodiment in many different
forms, there is shown in the drawings and described herein in detail a
specific embodiment with the understanding that the present disclosure is
to be considered as an exemplification of the principles of the invention
and is not intended to limit the invention to the embodiment illustrated.

[0046] It will be understood that like or analogous elements and/or
components, referred to herein, may be identified throughout the drawings
by like reference characters. In addition, it will be understood that the
drawings are merely schematic representations of the invention, and some
of the components may have been distorted from actual scale for purposes
of pictorial clarity.

[0047] Referring now to the drawings and in particular to FIG. 1, the
transmission line of the present invention is shown generally at 10.
Typically, such conductors are used to transmit and distribute high
voltage power forming the backbone of the national grid, for example. The
electrical conductor is typically strung between electrical poles and
towers 110 of varying sizes. The system operating voltages of such
electrical conductors typically ranges from 2,400 V to 765,000 V,
although not limited thereto. The transmission line includes conductor
12, messenger member 14 and coupling means 16. The conductor of the type
associated with the present invention is typically referred to as
stranded overhead transmission and distribution conductor.

[0048] Unlike commonly utilized transmission lines, wherein the conductor
encapsulates a strength member, such as a steel core, for example, with
the present invention, the conductor and the messenger are structurally
separate from each other and functionally independent relative to each
other. Specifically, conductor 12 comprises an aluminum stranded member
of a predetermined length (i.e., typically up to several hundred feet
long) having a plurality of strands, such as strand 20. The strands are
wound about each other, preferably with a slight helical winding. In the
embodiment shown, each of the strands 20 are substantially uniform in
cross-sectional area Inasmuch as there is no separate core member, the
conductor occupies the entirety of the cross-sectional area of the
conductor in a substantially uniform manner. In the embodiment shown, the
conductor may comprise aluminum or an alloy thereof (which may be heat
treated in any number of different manners, such as annealing, among
others). Other materials are contemplated, but typically, aluminum and/or
an alloy thereof is most preferred. Advantageously, as the strength
member is separated from the conductor, a relatively softer conductor,
with improved conductive capacity may be utilized, as the conductor is
not relied upon for its strength characteristics at splices and dead
ends.

[0049] Messenger 14 is shown in FIG. 1 as comprising a composite material
of a predetermined length (i.e., typically up to several hundred feet
long). The composite material may comprise one or more different fibers
22 which are embedded in a matrix 24.The fibers may comprise any one or
more of carbon fiber, glass fiber (including, but not limited to s-glass,
r-glass, s2-glass), basalt fibers, among others, which are embedded in a
resin matrix. In the embodiment shown, a single uniform fiber extending
longitudinally is contemplated. It is contemplated that instead of
extending longitudinally, the fibers may be helically wound at, for
example between 0 and 45 degrees, and more preferably between 0 and 5
degrees.

[0050] Inasmuch as the messenger is not surrounded by the conductor, as is
typically the case for high power transmission lines, the messenger, in
operation, is exposed to substantially lower temperatures and is
generally exposed to ambient along much of its surface. In many of the
embodiments, the messenger and the conductor are separated an appreciable
distance, such that the heat from the conductor has little effect to the
temperature of the messenger. The conductor may have splicing and/or dead
end connectors so as to join the various messengers.

[0051] To preclude conduction, the messenger comprises a composite wherein
the outer layer is insulative. In certain embodiments, especially where
carbon fiber is utilized, additional layers of fiber that are comprised
of material other than carbon fiber may be utilized as the outer layers.
In still other embodiments, a coating, such as a polymer coating, a tape
or a paint coating may be applied to the outside of the messenger to
insure the insulative effect.

[0052] Coupling means 16 is shown in FIGS. 2 and 3 as comprising bracket
members 40a, 40b, and bracket attachment assembly 46. The bracket members
40a and 40b are generally identical, and, as such, bracket member 40a
will be described with the understanding that bracket member 40b is
substantially identical. Bracket member 40a comprises an elongated
bar-like member which includes messenger indentation 42 and conductor
indentation 44 which are separated from each other a predetermined
distance. Preferably, the bracket comprises a molded fiber reinforced
member, or a metallic member. The indentations 42, 44 are generally sized
so as to receive half of the respective connector and/or messenger
therein. Thus, when the bracket members are coupled together, the
conductor is received in part by the conductor indentation of each of the
brackets 40a, 40b. Similarly, the messenger is received in part by the
messenger indentation of each of the brackets 40a, 40b.

[0053] It will be understood that the bracket members, in certain
embodiments, may be different in that they may have different indentation
configurations. In one such embodiment, the indentations of one bracket
may be smaller or substantially smaller than the indentations of the
other bracket (or one bracket may be planar, or without messenger or
conductor indentations). In such an embodiment, the conductor and the
messenger are retained to a greater extent in the indentations of one of
the two bracket members.

[0054] Attachment assembly 46 comprises suitable fasteners 50 which are
extended through openings, such as openings 48 in each of the brackets.
In the embodiment shown, the fasteners comprise nuts and bolts, whereas
in other embodiments, the two brackets may be riveted together, adhered
to each other, coupled to each other with pins, amongst other solutions.
In still other embodiments, the openings of one or both of the brackets
may be threaded so as to obviate the need for a separate fastener.

[0055] In another embodiment, and with reference to FIGS. 4 through 6, the
coupling means 16 may comprise a bracket member 140, messenger clamp
assembly 143 and conductor clamp assembly 145. The bracket member 140
includes messenger indentation 142 and conductor indentations 144. The
two indentations 142, 144 are separated from each other a predetermined
distance. Additionally, the two indentations may be lined with a rubber
material or another resilient member (such as a polymer). The bracket
member 140, itself, may be formed from a metallic member or from a molded
fiber reinforced member, without limitation.

[0056] Messenger clamp assembly 143 is comprises a first end which is
pivotably coupled to the bracket member 140 proximate the messenger
indentation 142. The second end of the messenger clamp assembly 143
comprises a fastener which is configured to engage the bracket member
opposite of the first end. The messenger clamp includes a rubber member
or other flexible member. Thus, when the messenger clamp is pivoted so
that the second end abuts the bracket member 140, the messenger is
captured between the messenger clamp and the messenger indentation of the
bracket member. The flexible members associated with each of the
messenger indentation and the messenger clamp assembly serve to cushion
the interface between the bracket and the messenger, so as to reduce the
damage imparted by one on the other. Additionally, the flexible members
become biased against the messenger and in certain circumstances preclude
the sliding of the bracket member along the messenger.

[0057] In a similar manner as with the messenger, the conductor is
maintained in position through interference between the conductor
indentation 144 and conductor clamp assembly 145. The conductor clamp
assembly is pivotably connected at its first end to the bracket member
and a fastener engageable with the bracket member is positioned at the
second end. Each of the conductor clamp assembly and the conductor
indentation include a rubber material or other flexible material
positioned therein. As with the messenger, the flexible members
associated with each of the conductor clamp assembly and the conductor
indentation cooperate to cushion the interface between the bracket and
the messenger, so as to reduce the damage imparted by one on the other.
Additionally, the flexible members become biased against the conductor,
and in certain circumstances preclude the sliding of the conductor
against the bracket member.

[0058] In another embodiment, shown in FIG. 7, the coupling means 16 may
comprise messenger tray assembly 220, conductor tray assembly 222 and
pivotable coupling assembly 224. In the embodiment shown, the messenger
tray assembly 222 comprises an elongated angled member which defines a
channel in which the messenger is positioned. A clamp member (not shown)
may be utilized to secure the messenger to the messenger tray assembly
after positioning of the messenger within the channel. In one embodiment,
the clamp member may comprise an elongated cap member which can be
clamped or secured to the messenger tray assembly so as to sandwich the
messenger therebetween.

[0059] Similarly, the conductor tray assembly 222 comprises an elongated
angled member which defines a channel in which the conductor is
positioned. A clamp member (not shown) may be utilized to secure the
messenger to the conductor tray assembly after positioning of the
conductor within the channel. In one embodiment, the clamp member may
comprise an elongated cap member which can be clamped or secured to the
conductor tray assembly so as to sandwich the conductor therebetween.

[0060] Pivotable coupling assembly 224 is configured to pivotably couple
the messenger tray assembly 220 and the conductor tray assembly 222. In
the embodiment shown, the pivotable coupling assembly comprises a pair of
ears extending from each of the messenger tray assembly 220 and the
conductor tray assembly 222 on opposing sides thereof. The corresponding
ears of the messenger tray assembly and the conductor tray assembly are
then coupled with a pin, rivet, fastener or other suitable member to
allow for pivoting therebetween. In other embodiments, such as the
embodiment shown in FIG. 8, a separate link 233 may be positioned between
the tray assemblies so that there are two points of pivoting between the
conductor tray assembly and the messenger tray assembly.

[0061] In yet another embodiment, a single messenger may be utilized to
support a plurality of conductors. One such embodiment is shown in FIGS.
9 and 10. In such a configuration, coupling means 16 comprises frame
member 310, messenger clamping member 312 and conductor clamping members
314, 316. Specifically, the frame member comprises a substantially planar
member having central region 320 and opposing wing regions 322, 324.
Clamping member 312 is coupled to the central region 320 and facilitates
clamped attachment to the messenger 14. In the embodiment shown, the
clamping member 312 comprises a conventional u-clamp. Of course, other
clamping members are contemplated, including the clamping members shown
and explained herein.

[0062] Each of the conductor clamp member 314, 316 comprises a conductor
tray assembly of the type shown in the embodiment of FIG. 7. The
conductor clamp members 314, 316 further include pivoting assembly 318,
320, respectively. Each pivoting assembly 318, 320 is substantially
identical, and, as such, pivoting assembly 318 will be described with the
understanding that it is substantially identical to the pivoting assembly
320. Specifically, the pivoting assembly 318 includes yolk link 330 and
pivot pins 332, 334. The yolk link allows for pivoting in two distinct
planes, namely one plane that is parallel to the plane defined by the
frame member 310 and one plane that is parallel to the respective
conductor. Thus, pivot pin 332 extends through frame member 310 and is
substantially orthogonal to pivot pin 334 that extends through the
opposing ears of the conductor tray assembly. In turn, the conductor is
able to pivot in two different manners relative to the frame member.

[0063] With reference to FIG. 13, in another embodiment, the phase
coupling means 16 may comprise a flexible housing member 352 which is
extended over each of the messenger and the conductor, when the same is
placed in a substantially abutting relationship. The coupling means 16
further includes armor grip clamp assembly 360 which comprises a pair of
semi-circular clamp members with openings for fasteners at either end
thereof. The semi-circular clamp members are positioned so as to overlie
the flexible housing member 352 at which time, fasteners are utilized to
couple the two semi-circular clamp members together. In the embodiment
shown, the flexible housing member comprises a rubber tubing, however,
other natural and synthetic polymer members are contemplated.

[0064] In a related embodiment, as is shown in FIGS. 11 and 12, in place
of the flexible housing member 352 of FIG. 13, a flexible liner 371 can
be utilized. The flexible liner may comprise a pair of members 373, 375
which are molded on the inner portion thereof to retain the messenger and
the conductor in a spaced apart configuration. The outer portion of the
flexible liners is configured to be grasped and retained by the
semi-circular clamps 376, 378. The clamps may further include surface
configurations, such as surface configuration 371 which interfaces with a
mating surface configuration of the flexible liner so as to register the
flexible liner relative to the semi-circular clamps, and to preclude
relative movement thereof upon installation.

[0065] Finally, in another related application, the coupling means may
comprise the helical winding of the conductor about the messenger, as is
shown in FIG. 14. In the embodiment shown, the helical winding is such
that one winding corresponds to approximately nine feet of the messenger.
In other embodiments, such a configuration may be limited to a lesser or
greater length. As set forth above, the messenger of the present
embodiment is not conductive such that the electrical load is carried by
the conductor and not by the messenger. It is contemplated that the
elongated messenger tray may be utilized to couple the messenger to an
outside structure, such as a tower or pole.

[0066] Advantageously, in the above-identified embodiments, the load
bearing messenger and the current carrying conductor are separated and
isolated from each other. As such, an independent design of each is
allowed, as there is no dependence on the load bearing properties of the
conductor or the current carrying of the messenger. As the conductor
consists entirely of aluminum (i.e., no steel core or composite core as
is used in conventional core-based transmission lines), the
current-carrying capability of the conductor at any give diameter is
increased. The geometry of the messenger can be varied without regard to
the structure of the conductor. Inasmuch as the messenger comprises a
insulative member, current division between the conductor and the
messenger is eliminated. Furthermore, by separating the messenger from
the conductor, the heat of the conductor minimally effects the messenger.
In turn, less expensive mechanical grades of fibers may be utilized for
the messenger, as the heat capacity of the messenger is reduced.
Similarly, high Tg resins are typically not required, as the messenger is
outside of the current carrying path and is exposed along most of its
length to ambient air.

[0067] Furthermore, due to the separation, it is typically not necessary
to coordinate the coefficient of thermal expansion of the messenger to
that of the conductor. Additionally, the conductor will typically be
subject to a much different range of temperatures. For example, the
conductor may be in the range of 200° C. while the messenger may
be at half of that temperature, or less. Additionally, the line sag is
generally controlled by the messenger, as one span of the messenger may
include or support five sub-spans of the conductor.

[0068] Furthermore, as the conductor is generally not under full tension
(while the messenger is subjected to full tension), full tension splices
and dead ends are preferably required only for the messenger. Due to the
increase in current carrying capacity with little to no increase in
weight, the conductor of the present invention is well suited as a
replacement to conventional conductors, through, for example
reconductoring. In particular, additional structures and right of ways
are not necessary. Of course, other advantages than those identified
herein are contemplated.

[0069] The foregoing description merely explains and illustrates the
invention and the invention is not limited thereto except insofar as the
appended claims are so limited, as those skilled in the art who have the
disclosure before them will be able to make modifications without
departing from the scope of the invention.